Touch-entry user input device

ABSTRACT

A touch-entry user input device having a first mode in which the device does not perform a first function and a second mode in which the device does perform the first function wherein the device has means for user input and is arranged, when in the first mode, to initiate exit from the first mode and entry into the second mode at the initiation of a user input.

The present invention relates to a touch entry user input device. Itparticularly relates to a touch entry user input device located remotelyfrom the device to which input is supplied.

Currently mobile phones have an integrated touch-entry user input, suchas a keypad. A key of the keypad may have a different function dependingupon the manner in which it is actuated. For example, when the phone isbeing used for text entry a single actuation of a key can produce aparticular character and the repeated actuation of the key in rapidsuccession can produce different characters. Also, when the phone is inidle mode, the actuation of a key by depressing and releasing the keyproduces a numeric character as part of a telephone number to be dialedand the actuation of the same key by depressing the key for a durationexceeding about 1 second and then releasing it instructs the phone todial a stored number. This is called “one-touch” dialing.

The Bluetooth (Trademark) standard describes how low power radiotransceivers can be used to remotely communicate over a range of tens ofmetres. These low power transceiver devices are already present in somemobile phones and can be used to allow a user input (e.g. a cordlessheadset) to be used remotely from the mobile phone. Communicationbetween the headset and the phone occurs between a low power radiotransceiver in the headset and the low power radio transceiver in thephone. A particular advantage of Bluetooth transceivers in mobileapplications is that they have energy conservation modes which prolongbattery life.

It would be desirable to improve existing user input devices, inparticular, touch-entry input devices comprising Bluetooth transceivers.

According to one aspect of the present invention there is provided atouch-entry user input device having a first mode in which the devicedoes not perform a first function and a second mode in which the devicedoes perform the first function wherein the device has means for userinput and is arranged, when in the first mode, to initiate exit from thefirst mode and entry into the second mode at the initiation of a userinput.

According to another aspect of the present invention there is provided amethod of transferring a user input device in response to user inputfrom a first mode in which the device is not capable of performing afirst function to a second mode in which the device is capable ofperforming a first function where there is an inherent delay in thetransfer process, comprising the steps of: detecting the initiation ofuser input and then immediately initiating the transfer.

For a better understanding of the present invention reference will nowbe made by way of example only to the drawings in which:

FIG. 1 illustrates a touch-entry user input device 2 according to oneembodiment of the present invention and

FIG. 2 illustrates timing.

According to the Bluetooth Standard, transceiver devices communicate byforming a piconet. A transceiver device can operate as either a Masteror a Slave. When operating as a Master, the transceiver controls thepiconet and the timing of the piconet is synchronised to the timing ofthe Master. Communication in the piconet occurs using packets in a timedivided manner with only one device transmitting in any one time slot.The time slot is 625 microseconds duration. The Master assigns an ActiveMember Address AM_ADDR to each Slave participating in the piconet andtransmits to and receives from any one of the participating Slavedevices using the appropriate AM_ADDR. It can transmit in the even timeslots and can receive in the odd time slots. When operating as a Slave,the transceiver can communicate with only the Master of the piconet. Itreceives in one slot and transmits in the next slot.

When a Slave is in the Active Mode, it is participating in the piconet.It has an AM_ADDR and keeps synchronised to the Master. It continuallylistens to receive packets addressed to it. It can transmit packets tothe Master.

When a Slave is in the Sniff Mode, it has an AM_ADDR and keepssynchronised to the Master. The Master sends a ‘sniff’ packet to theSlave once every ‘sniff interval’ Tsniff. The inventor has realised thatthere is a variable delay D between when a Bluetooth transceiver decidesto exit the Sniff Mode and when it enters the Active Mode. The inherentvariable delay D includes the variable period before the device is ableto receive a ‘sniff’ packet (and is therefore able to transmit a messageto initiate exit from the Sniff Mode) and the time taken to exit theSniff Mode. The variable period may be as long as Tsniff. The time takento exit the Sniff Mode is the time required to transmit the message tothe Master and to receive a message in reply.

When a Slave is in the Park Mode, it gives up its AM_ADDR It is not ableto transmit data to the Master. The Master controls the Slave to movefrom a Park Mode to an Active Mode by transmitting an ‘unpark’ packet tothe Slave once every ‘park interval’. The Slave, while parked, regularlylistens for an ‘unpark’ packet addressed to it and sent by the Masterand in the regular ‘park intervals’ between these attempts is switchedoff. The inventor has realised that there is a variable delay D betweenwhen a Bluetooth transceiver decides to exit the Park Mode and when itenters the Active Mode. The inherent variable delay D includes thevariable period before the device receives an ‘unpark’ packet (and isable transmit a message to initiate exit from the Park Mode) and thetime taken to exit the Park Mode. The variable period may be as long asthe ‘park interval’. The time taken to exit the Park Mode is the timerequired to transmit a reply message to the Master.

The inventor has realised that when the touch entry device is capable ofdiscriminating between an instantaneous depression of a key and acontinuous depression of a key lasting more than a threshold T, it maytake the device at least the threshold T to discriminate a user input.Therefore there will be a delay between the user first making an inputkeystroke, when the input device is in the Sniff or Park Modes, and theresponse from the device to which the entry is transmitted of thethreshold T (for discrimination) plus the variable delay D (for enteringthe Active Mode).

The inventor has developed an effective yet simple solution to theproblem of a long variable delay. The delay D is made less than thethreshold and a decision to exit the Sniff/Park Mode and enter theActive Mode is made before the keystroke input has been discriminated.The threshold is typically 0.8 seconds and the delay D is made less thanthis, for example, by setting Tsniff and the ‘park interval’ to lessthan 0.8 seconds and preferably 0.5 seconds. Preferably, the decision toexit the Sniff/Park Mode and enter the Active Mode is made at thebeginniug of the keystroke and the Active Mode is entered before theuser input has been discriminated.

FIG. 1 illustrates a touch-entry user input device 2 according to oneembodiment of the present invention. The touch-entry user input device 2comprises a processor 4 connected to a low power radio transceiver 6which communicates in accordance with the Bluetooth Standard, and to akeypad 8 of user depressible keys. The touch-entry user input device 2operates as a Slave or a Master in a Bluetooth piconet. The user caninput data or commands using keystrokes on the keypad 8. The processor 4detects and identifies each keystroke and controls the low power radiotransceiver to send a radio packet comprising data identifying akeystroke to a remote device (not shown).

The touch-entry user input device 2 has a first operational mode (anenergy conservation mode) in which the low power radio transceiver 6 isin the Sniff Mode or the Park Mode and is not readily capable oftransmitting keystroke data. The touch-entry user input device 2 has asecond operational mode (a radio communication mode) in which the lowpower radio transceiver is in the Active Mode and is readily capable oftransmitting keystroke data.

The interval in the Park Mode is 0.5 seconds and Tsniff is 0.5 seconds.

The processor 4 is programmed to detect, when the device is in the firstmode, the initiation (as opposed to completion) of a user inputkeystroke. The detection of the keystroke occurs at the same timeirrespective of whether the keystroke is an instantaneous depression ofa key, a continuous depression of a key or a repetitive depression of akey. When the processor 4 detects the initiation of a keystroke itautomatically and immediately initiates the exit from the first mode andentry into the second mode. The processor 4 initiates the exit byinstructing low power radio transceiver 6 to exit the Sniff Mode or ParkMode. The low power transceiver 6 exits the Sniff Mode by transmitting aLMP_unsniff_req message and receiving a LMP_unsniff_accepted messagefrom the Master in reply and data can be transmitted immediately. Thelow power transceiver 6 exits the Park Mode by receiving aLMP_unpark_BD_ADDR_req or LMP_unpark_PM_ADDR_req message from theMaster. This provides an AM_ADDR to the slave. The slave replies bytransmitting a LMP_accepted message to the Master and the Park Mode isexited.

The processor 4 is also programmed to discriminate between aninstantaneous depression of a key, a continuous depression of a key anda repetitive depression of a key. A continuous depression is one lastingmore than a threshold, for example 0.8 seconds. Once the keystroke hasbeen discriminated, the processor instructs the low power radiotransceiver to send a message identifying the keystroke. If the deviceis in the first mode when a keystroke is made, the initiation of theexit from the first mode is completed before discrimination of the userinput. Preferably, the entrance into the second mode has been completedbefore the discrimination of the user input. Thus once the keystroke hasbeen discriminated the message identifying it may be sent immediately.

FIG. 2 illustrates the timing. The trace (a) illustrates the timing ofthe depression of a key. The key is depressed for time t (t=T3−T1). Thetrace (b) illustrates the timing of the Active Mode. The trace (c)illustrates the timing of keystroke message transmissions. At time T1,the user starts to press the key. At time T2, the touch-entry user inputdevice 2 enters the Active Mode. At time T3 the user input keystrokeends and is discriminated and a message identifying the keystroke issent. Therefore the reaction times when using a remote touch-entry userinput device are reduced. Furthermore, the time at which the messagecontaining the keystroke is sent does not vary.

Although the invention has been described in the preceding paragraphswith reference to various examples, it should be appreciated thatmodifications and variations to the examples given can be made withoutdeparting from the scope of the invention as claimed.

Whilst endeavouring in the foregoing specification to draw attention tothose features of the invention believed to be of particular importanceit should be understood that the Applicant claims protection in respectof any patentable feature or combination of features hereinbeforereferred to and/or shown in the drawings whether or not particularemphasis has been placed thereon.

1. A touch-entry user input device having a first mode in which thedevice does not perform a first function and a second mode in which thedevice does perform the first function wherein the device has means foruser input and is arranged, when in the first mode, to initiate exitfrom the first mode and entry into the second mode at the initiation ofa user input.
 2. A touch-entry user input device as claimed in claim 1comprising detection means for detecting the initiation of a user inputand control means for initiating the exit from the first mode.
 3. Atouch-entry user input device as claimed in claim 1 wherein the firstmode is an energy conservation mode.
 4. A touch-entry user input deviceas claimed in claim 1 wherein the second mode is a low power radiocommunication mode.
 5. A touch-entry user input device as claimed inclaim 1 wherein the means for user input comprises a user depressiblekey.
 6. A touch-entry user input device as claimed in claim 5 comprisingdiscrimination means for discriminating an instantaneous depression ofthe key from a continuous depression of the key.
 7. A touch-entry userinput device as claimed in claim 1 wherein the initiation of the exitfrom the first mode occurs before discrimination of the user input.
 8. Atouch-entry user input device as claimed in claim 1 wherein the entryinto the second mode occurs before discrimination of the user input. 9.A touch-entry user input device as claimed in claim 1 further comprisinglow power radio transceiver means and wherein the exit from the firstmode is initiated by sending a message using the low power radiotransceiver means.
 10. A touch-entry user input device as claimed inclaim 1 further comprising low power radio transceiver means wherein thefirst function comprises transmitting data using the low power radiotransceiver means.
 11. A touch-entry user input device as claimed inclaim 1 operating as a Slave in a Bluetooth piconet.
 12. A touch-entryuser input device as claimed in claim 1 operating in accordance with theBluetooth Standard wherein the first mode is the Sniff Mode or ParkMode.
 13. A touch-entry user input device as claimed in claim 12 whereinthe exit from the Sniff Mode is initiated by transmitting aLMP_unsniff_req message.
 14. A touch-entry user input device as claimedin claim 12 wherein the exit from the Park Mode is initiated bytransmitting a LMP_accepted message.
 15. A touch-entry user input deviceas claimed in claim 1 operating in accordance with the BluetoothStandard wherein the second mode is the Active Mode.
 16. A touch-entryuser input device as claimed in claim 1 wherein the time taken to exitfrom the first mode and enter into the second mode is less than the timetaken to discriminate a user input.
 17. (canceled)
 18. A method oftransferring a user input device, in response to user input, from afirst mode in which the device is not capable of performing a firstfunction to a second mode in which the device is capable of performing afirst function where there is an inherent delay in the transfer process,comprising the steps of: detecting the initiation of user input and thenimmediately initiating the transfer.
 19. A method as claimed in claim18, wherein user input is performed by depressing a user depressiblekey.
 20. A method as claimed in claim 19, further comprising the step ofdiscriminating an instantaneous depression of the key from a continuousdepression of the key.
 21. (canceled)